Design of Solar Thermal Power Plants

Read from local Zotero full-text PDF (group 5183627 / Joule Heist).

(Book — read TOC, preface, introduction, and collector/concentrator chapters only; not read cover-to-cover.)

Key findings

• Scope: CSP plant design for water/steam working medium; receiver output power 8-800 t/h, condensing steam turbine capacity 1-100 MW. Concentration modes covered: parabolic trough, power tower (central receiver), linear Fresnel, parabolic dish.
• Concentrator/concentration-field cost is the dominant capital item: solar tower and parabolic trough concentrator systems account for 45-70% of primary investment; annual mean concentration-field efficiency is normally 58-72%.
• A 1% improvement in CSP system efficiency lowers the levelized cost of electricity by ~8% and reduces total capital investment by 5-6%.
• Parabolic trough was the first CSP technology to reach commercial operation (1980s), with max stable plant capacity up to ~80 MW; paraboloid concentration ratio is low (70-80), limiting heat-transfer-fluid temperature and system efficiency.
• Parabolic trough receiver tube: ~4 m long; inner metal tube ~70 mm OD, outer glazed shield tube 115-125 mm OD, with vacuum interlayer, getter, and metal-glass seals. Heat transfer fluid is water/steam, synthetic oil, or molten salt.
• Power-tower receiver flux: example peak flux density was 80 kW/m2 at 20 cm from the focal point and 350 kW/m2 at the focal point — a value crucial to receiver material and structural design.
• Heliostat specular reflectance ~0.93-0.94 when clean; at Badaling, dust dropped it from 94.6% (Aug 23) to 45.5% (Oct 10), then rain restored it to 82.1% (Oct 13) — quantifying soiling losses. Annual-mean efficiency of water/steam tower systems can exceed 15%; molten-salt systems enable higher-parameter (supercritical) operation.
• Land coverage: parabolic trough field ~2.5x total aperture area; solar tower field 4-6x heliostat aperture area. Dish-Stirling: concentration ratio 600-3000, operating temp up to 750 degrees C, peak solar-to-power net efficiency up to 30%, unit power 5-50 kW.
• Global CSP context (2018): 5206 MW grid-connected worldwide, 1048 MW under construction, 3691 MW under development. IEA roadmap projects 1089 GW cumulative by 2050 at ~50% capacity factor (4380 h/yr). Ivanpah tower plant total capacity 392 MW (three towers, each >130 MW).
• China’s annual solar irradiation ~1050-2450 kWh/m2; ~300,000 km2 of Gobi Desert (~23% of China’s desert area) usable for solar power. Solar multiple defined as ratio of solar-field net thermal power at design point to power-block thermal demand at rated power.